Apparatus for combining finely divided substances



Nov. 28, 1950 H. M. coLLlNs ETAL 2,532,224

APPARATUS FOR COMBINING FINELY DIVIDD SUBSTANCES Filed Feb. 3, 1949 Hmmm# Mmmm @mms u www? Patented Nov. 28, 1950 UNITED STATES PATENT OFFICE APF'ARATUS FOR COMBINING FINELY DVDED SUBSTANCES Henry M. Collins, Vaughan rEownship, Ontario, and Charles Douglas Wright, Toronto, Ontario, Canada, assignors to Reliable Plastics Company, Limited, Toronto, Ontario, Canada Application February 3, 1949, Serial No. 74,288

4 Claims.

curtain of the injected substances directed in a manner about an exhaust port to ensure the removal of the gas from the mixing vessel with out entrainment of solid particles.

This application is a continuation-in-part of application Serial No. 687,302, filed July l2, 1945, patented April 4, 1950, No. 2,502,778 in the names of Henry M. Collins and Norman E. Adcock.

It is well known that finely divided powders may be rendered homogeneous by means of a tumbling process. Moreover, it is also known that any liquid which is compatible with one or more of these powders may be sprayed or aspirated into the powder charge at a relatively high rate of introduction, and the liquid will be completely absorbed into the powder particles. The most convenient, and usual method of introducing the compatible liquid is by forming a mist, or spray of the liquid, and injecting this spray into the powder mass in a jet of hot air or hot nitrogen.

Heretofore, the main difficulty has been to provide means for the escape of the injected air or nitrogen without allowing escape of the nely divided powder. Where une screens or air permeable cloth have been used, it has been found that the dust particles invariably either pass through the filter, or clog the pores completely, stopping the process and possibly causing dangerous pressures in the tumbler.

Similarly where porous packings or composition plates have been used, blocking has invariably occurred. Where large enough interstices have been provided to prevent blocking, considerable amounts of ne powder have been allowed to escape.

Itis a particular object of the present invention to provide a filtering curtain which is highly ecient and which involves a gaseous spray which envelopes or touches the `marginal edges of the exhaust oriiice of an enclosure, the curtain being formed by the introduction of a gas stream into said enclosure by way of an entry port.

With this and other objects in view the invention is applicable `to a process for homogeneously combining iinely divided substances where at least one of the substances is tumbled in a container or enciosure. Gaseous liuid is injected into the container by means of an inlet port, the container having an exhaust port adjacent the inlet port. The inlet port is designed to inject the gaseous fluid in such manner that an enveloping curtain is formed which touches the marginal edges of the exhaust port thereby forming a wall of gaseous fluid, that is to say said curtain, between the interior of the container and the exhaust passage. Therefore, as gaseous fluid is injected into the container excess gases will be displaced and caused to flow out of the exhaust port, but in order to do so much first pass through said curatin of gaseous iiuid whereby entrained par ticles vwill Abe removed from the excess gases to be exhausted.

One general embodiment of the invention is described with reference to the accompanying drawings in which:

Figure 1 illustrates a partial sectional view of a tumbler according to the present invention.

Figure 2 is a face view of the arrangement of the inlet port, that is to say, the plurality of nozzles which direct the injected gaseous fluid to form a lter curtain, this ligure also revealing the section line 2-2 of Figure l.

Figure 3 is a side view on a reduced scale of a tumbler comprising the present invention.

Figure 4 illustrates an enlarged sectional view of one of the double tubes used in the nozzle members.

Figure 5 is a sectional view of a simple type of nozzle which forms a single inlet port providing a curtain of gaseous fluid while injecting the same, the curtain isolating the exhaust port. This ligure also shows a different form of conflicting shield.

Figure 6 is a further alternative form of inlet port and exhaust port arrangement. Referring now more specifically to the drawings, lil is a barrel-type tumbler having lixed at either end the massive bushings ll, rotatably mounted on the stationary bracket support l2 (see Figure 2) which in turn, slidably mounts the stationary adjustable sleeve I3. An inwardly extending sleeve ld extends from the bushing H to form an inner housing.

A series of double concentric tubes l5 lead from a source of gaseous uid such as air pressure, and source of liquid to be introduced to the tumbler and terminate in spray jets or nozzles I6 which are of any variety known, such as used at present for producing a spray of finely divided droplets. In the tubes l5, the air may be passed through the annular space [5a between the walls of the two tubes and the liquid may be passed through the central tube leb. The tubes is are mounted within the annular chamber Il by pass.-

ing through the chamber wall I8 which extends from connection to the sleeve I3 and forms an integral part of the walls I9 of the exhaust passage 20. The remaining wall of chamber Il is formed by the spaced apart walls 2| which support the sealing ring 22 by means of the separating ring 23- and which are iixed relative to the sleeve I3 and have suitable ports (not shown) to accommodate the conical confining shields 24 which receive the nozzle I6 substantially as indicated.

The flow of gaseous fluid from the inlet port (that is to say, a plurality of nozzlesvor a single nozzle of suitable design as the case may be) into the container by virtue of the design and position of the particular nozzle or nozzles employed, forms a curtain of gaseous fluid 25 which touches the marginal edge at least, of the exhaust port 25. The shield 2l which extends from the spaced Walls 23 by means of the supporting member 2S serves as a' means for'deflecting the injected gases and directing them in the desired manner. The shape of the shield 2 is determined by the manner in which'it is desired that the injected gases be deflected.

Due to pressures built up by the injected sub stances,l a certain amount of nnely divided material will tendto pass the sealing ring l2 and ultimately nd'its way into the chamber Il' unless great pains are taken in the workmanship inthe assembly of the components. In order to obviate any dimculties which might arise in this connection, I prefer according to the invention to include the'feature of a port Ila in wall I8 communicating with' the chamber i? and having the fitting Ilb. Compressed air through this tting provides pressures in the chamber Il inexcess of the pressures exteriorly thereof. associated with the injection of the nely divided substances into the tumbler id.

Figure illustrates a modified arrangement having a substantially circular shield 2S disposed in the path of the injected gaseous fluid 3i) which emanates from the inlet port 3l which is in the form of an annular orifice 32 formed by the outer housing 33`with its depending lip 34 in spaced apart relation to the inner movable member S5, the latter having an exhaust passage 36 communicating with the exhaust port 3l. The annular chamber 38 is fed inlet gaseous fluid by way of suitable. port 39. As the gaseous iuid is projected from the annular opening or orice 32, a substantially conical curtain lid of gaseous fluid is formed, isolating the exhaust port 31.v We do not recommend` this form of single nozzle mainly because certain difficulties may be encountered in injecting a gaseous fluid along with a powdered material, but where a gaseous fluid alone is injected ora fluid proper, then this particular nozzle device will be found suitable. The present invention, however, does not relate to the specific form of nozzle used for the inlet port, and the development of the nozzle shown in Figure l has been found most suitable forv all practical purposes;

A furthertype of nozzle may be'used however, substantially as disclosed in Figure 6 wherein the member I has a central bore #i2 and a cooperating nozzie member i3 designed to cause fluidpassing through the annular passage M to form a curtain fiwhich extends to deect oli the shield 46. The latter is preferably mounted on attrib@ di: whichsin turn mounts the tting d3, Which has a central bore 155 which serves as an exhaust port.'

Bil

f outV loss of the powder.

We therefore specify that the terms nozzle or "port in the singular sense, shall also, but not necessarily, include the plural meaning since it is obvious that the curtain of gaseous fluid which We have described may be formed by a plurality of` nozzles as in Figure l, or a single nozzle or entry port as shown in Figures 5 and 6. It is essential that the curtain of gaseous iiuid formed isolate the exhaust port so that excess gases will be required to penetrate the curtain in order to find their way to the exhaust port. We also define that the phrase touching the marginal edges of said exhaust port shall mean, for the purposes of claiming my invention, that the curtains 25, iii or i5 touch the marginal edges ofthe body of material carrying the outlet port or extensions thereof such as the shield 45 in Figure 6.

It will be readily appreciated that the present invention has a wide application in iields other than those indicated, and could be used toad- Vantage in any process where substances-are to be hemogeneously added to any finely dividedpowder, and where gases must be exhausted with-- For the purpose of general example in this respect, the invention' is applicable to the addition of liquid perfumes to talcum or face powder.

The composition of the jetl which is introducedl from the nozzles obviously may be variedsothat it includes one or more materials to be addedto` the powder charge, or on the other hand-only heated air or nitrogen for dryingthe powder'. In short, without. departing from the spirit of the invention, a gas, a mixture of gases, a mixture of gases and liquids, a mixture of gases andnnely divided solid particles for the above purpose is` obviously within its scope. It includes the additionofany suitable gaseous uid.

What we claim asour invention is:

1. Apparatus for the treatment of nely divided substances comprising, an enclosure, means for rotating said enclosure, an exhaust port at one` end of said enclosure aligned with the axis of rotation thereof, a fluid inlet port including means arranged about said exhaust port and said axis for injecting a curtain of gaseous fluid into said enclosure and directing said curtain to touchthe complete periphery of the exhaust port in aA manner to isolate the exhaust port from the interior of the enclosure whereby excess gases must pass through the injected curtain of gaseous, 1iuid= for exit from the enclosure through said exhaustY port.

2. Apparatus for the treatment of finely divided substances comprising, an enclosure, means for rotating said enclosure, an exhaust port for said enclosure, a fluid inlet port for injecting,f`

gaseous iiuid into said enclosure and including' means arranged about saidexhaust port and said axis for forming said gaseous fluid into acurtainl extending across said enclosure and dividing the same into a'primary treating chamber and a sec*- ondary chamber wherein the secondary-chamber is in direct communication with said exhaust port.

3. Apparatus as claimed in claim 2 and means for supplying compressed air to the secondary chamber at a pressure greater than the-pressures in said primary chamber.

4. Apparatus for treatment of nelydivided substances comprising the combination of a roL tatable enclosure designed to enclose a charge of' finely divided substances, an exha-ustport at oneend. of said; enclosure aligned with the axis or.y

2,532,224 5 6 rotation thereof, a, plurality of injection nozzles REFERENCES CITED arranged aboflt Said exhaust por? and sal@ axls The following references are of record in the and forming inlet ports for the introduction of me of this patent. gaseous fluid into sa-id enclosure, said nozzles being thereby disposed to direct the injected gaseous 5 UNITED STATES PATENTS Huid between the charge of finely divided sub- Number Name 'Date stances and the exhaust port in a manner t0 1,196,595 Sharpe Aug. 26, 1916 cause a curtain of gaseous uid to be formed 2,292,897 Nielsen Aug. 11, 1942 which physically touches the outer periphery of 2,306,962 Kropp Dec. .29, 1942 the exhaust port to isolate the latter from said 10 charge whereby the injected gaseous fluid forms FOREIGN PATENTS an effective lter curtain in advance of and Number Country Date across said exhaust port. 57,144 Denmark Jan. 15, 1940 HENRY M. COLLINS. CHARLES DOUGLAS WRIGHT. 15 

